Some oil and gas wells are completed in unconsolidated formations that contain loose fines and sand. When fluids are produced from these wells, the loose fines and sand can migrate with the produced fluids and can damage equipment, such as electric submersible pumps (ESP) and other systems. For this reason, completions can require screens for sand control.
Horizontal wells that require sand control are typically open hole completions. In the past, stand-alone sand screens have been used predominately in these horizontal open holes. However, operators have also been using gravel packing in these horizontal open holes to deal with sand control issues. The gravel is a specially sized particulate material, such as graded sand or proppant, which is packed around the sand screen in the annulus of the borehole. When applied, the gravel acts as a filter to keep any fines and sand of the formation from migrating with produced fluids.
In a gravel pack assembly for a horizontal open hole, proper linear spacing of an inner service tool relative to outer components of the assembly can be particularly important. Operators typically run fixed pipe lengths down the assembly and rely on pipe tallies and available pipe lengths to determine the correct space out for the service tool in the assembly. Unfortunately, the lengths of any screens and the service tool in the horizontal open hole can be considerable, and relying on pipe tallies to achieve correct spacing may prove difficult.
Additionally, the service tool for a gravel pack assembly is typically moved to perform various functions during gravel pack operations. Due to well depth, deviation, tubing stretch, friction, and the type of gravel pack completion to be run, determining the position of the service tool downhole in the assembly can be very difficult. This is especially true in long horizontal gravel pack completions. In the end, pumping of sand slurry when the tool is in an incorrect position in the assembly can cause the service tool to stick and can have catastrophic consequences.
Typically, mechanical indicating collets have been used in the prior art to locate the service tool in the assembly. Additionally, “smart” collets have been used, which reciprocate between a relaxed position and a propped position for positive identification of the service tool's location. Unfortunately, mechanical indication may not always work due to high drag forces and other issues involved in moving the service tool in the downhole assembly.
The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.